Chess opening principles can help most players escape sub-900 rating with time and practice implementing:
https://www.chess.com/blog/KeSetoKaiba/opening-principles-again
However, more important than the rating numbers here is the mindset. First of all, every fairly serious chess player knows the feeling and it isn't rare either; there will be MANY times where you go on losing streaks or huge downswings. The key is to focus on learning chess and not focus too much on the rating. The feeling of losing and not knowing what is wrong is completely normal and most everyone experiences it, so you aren't alone and nothing specific may even be wrong!
Here is something worth realizing: If you are 900 rating and drop to 800 rating in one day (hypothetically but true for any rating drop), then you are NOT 100 points weaker now. You are not 100 points less knowledgeable. You are not 100 points less intuitive. All that happened is you happened to lose 100 points of some rating formula which estimates anyway. You are the same you!
One may find comfort in knowing that you constantly gain experience and especially true for losses. Not to sound a downer (hope this motivates instead), but every fairly serious chess player will have MANY of these moments they are feeling at a loss of what to do.
@Hikaru (GM Hikaru Nakamura) once said on a live chess stream something like, "The most important skill to becoming a chess grandmaster is probably the ability to learn from your chess losses; not only the information to improve, but also using those losses to motivate you to get better."
Good luck with your chess and feel free to message me if you want to chat chess or ask a chess question or something, but basically what you are feeling now is not fun at all, but everyone goes through it at some point, so at least you aren't alone...the good moments chess brings due make up for the tough times though
I have no idea what is wrong with me, but I cannot escape sub 900 and stay out. I am losing games for no reason whatsoever and I feel like I've regressed enormously in the last 3 weeks of play. I feel like giving up on the game entirely because I cannot string together any good games that aren't won on total blunders I get lucky to capitalize on.